It is very easy to activate the WPS on your router.
1
Activate the WPS on your main mesh unit
To do so, press the WPS button on the Mesh unit that is connected to your router/modem by RJ45.
2
Internet Settings
Now go the the Network selection of your device (phone, computer, printer, etc.) and the new device added to the network should appear, and you can now connect to its network.